Hydraulic stop for gun mount systems



Aug. 24, 1948. J, TRQTTER 2,447,968

HYDRAULIC STOPS FOR GUN MOUNT SYSTEM Filed June 18, 1945 INVENTOR JOHN C. 7Z20TTER Patented Aug. 24, 1948 UNITED STATES "PATENT OFFICE HYDRAULIC STOP FoR GUN MOUNT TSYSTEMS John C. 'Trotter,-Williamsvilic, N. Y., assignor in Bell Aircraft ICorporation, Buffalo, :N. TY.

8 Claims. 1

This invention relates to ordnance, and more particularly to improvements in powered "aim control means for flexibly mounted machine guns, cannon, or the like. More specificallythe invention relates .to hydraulically actuated gun mounts and to improvements in aim adjustment movement stop means for use in conjunction therewith.

It is an object of the present invention to provide a hydraulic gun mount mechanism .incorporating an improved automatic valveme ans adapted to be actuated'upon movement of the mounted gun into a'prescribed limit ofaim adiustment position. Another object .of the invention is to provide an improved hydraulic control system of the character described'incorporating an automatic stop valve mechanism whichpermits reverse direction flow .of hydraulic fluid through the system subsequent to each gun travel stoppage. Another object is toprovide an improved stop mechanism for the purpose referred to which operates to avoid jammin of the .mechanical parts so as to permit free reversal of the gun training direction. Other objects .and advantages of the invention will appear from the specification hereinafter.

In the drawings:

Fig. 1 is a fragmentary elevation of a gun mount and gun aim control arrangement'of the invention; and

Fig. 2 is 'a section through a travel stop "valve member of the mechanism.

The drawings illustrate the invention in coniunction with a gun mountembodied in a turret carried at the lower nose portion of an aircraft fuselagewhich is indicated generallyat Iii. However, it will be understood that the invention is not limited to such an application or :to use upon aircraft, or in connection with the specific type of mount shown and'described hereinafter; and that the drawing illustrates only one example of application of theinvention.

The gun turret of the drawing comprises a bowl-shaped enclosure I 2 carried by a ring "M which mounts by means of rollers'upon ana'n'nula r base 16. Thus, the turret'isfreely rotatable, unless otherwise restrained, about a vertical axis disposed centrallyof the turret, whereby the supported gun battery may be rotatedas a unit for azimuth adjustments --of the gun battery -aim. One or more cannon 'or 'guns or machineguns as indicated at l8 are arranged to be'nrounted upon the turret frame 14 "by means of'a forked bracket device 28 extending irigidly from the frame. A gun mount frame consisting crime!- mount frame.

aim adjustment travel in traverse.

connected struts" and as indicated generally at 22 is suspended :from the bracket 20 by means of paired stirrups 24 extending :from the frame 22 *at opposite sides of the gun battery into pivotal connection with bearingportions 26 of the bracket 2!], whereby to enable the gun and gun mount unit to be freely pivotable'about a horizontal axis extending through the bracket bearing portions 26-26 "at opposite sides of the gun The turret enclosure l2 will 'be vertically slotted at positions in registry with movement of the gun-barre1s,-whereby it will be understood that the aim of the gun battery may be readily adjusted in elevation by actuating the gun mount frame to pivot about the axis of the bearings 26-26. Thus, the gun battery is mounted relative to the supporting vehicle so as to 'be universally adjustablefor aiming purposes.

To procure aim'adjusting movements of the gun battery relative to the 'base l6, motor means as indicated at 28 will be-carried by either the ring 44 or the base F6 andoperationallyconnected to the otherasby-gearingwhereby ODeIationOf the motor will procure relative movement between the turret and the base to give the gun battery Similarly, motor means will be provided to be carried by the gun *moun't bracket 20 to engagewith'the gun moun't frame to'procure relative movement there- -between for causing the gun mount frame 22 to rotate relative to -'-the -bracket 20 about the horizontal axis of the bearings 26-46, for elevational aim adjustment purposes.

The' present invention deals with improvements in hydraulic motor control devices for such purposes, and therefore-the azimuth control motor 28 and the elevational aim control motor as indicated at 30 are intended to be illustrated to comprisehighspeed hydraulicmotors. The motor 30 is shown-as being carried upon a portion '32 'of the bracket 20,-andthe drive shaft of the motor -30 is arranged "to extend into driving connection with a toothed sector 34 carried by the stirrupsid-Mof the "gunmount frame, as by means "or a worm gear 36. .Thus, it will be understood within convenient reach of the gun battery operator, as at a position remote from the turret within a gunners compartment portion of the airplane fuselage; and it will be understood that any suitable control handle and valve and generator mechanism may be employed. However, a suitable control mechanism of the character referred to has been illustrated and described in detail by me in my patent application issued November 11, 1947 as Patent No. 2,430,747. Paired conduits 46-41 lead from the pressure generator 46 into connection with the motor 30. Another pair of conduits 48-48 lead from the generator 40 to the traverse control motor 28 to provide controlled operation thereof.

To automatically stop the gun battery elevational aim adjustment travel at prescribed limits thereof, a pair of valve devices are carried, as indicated generally at 58-58 by the turret bracket 32, and are so arranged as to have actuating stem portions extending therefrom into the path of elevational aim adjusting travel of the gun battery. Hence, upon arrival of the gun battery at the prescribed maximum muzzle-depressed position thereof, the control stem portion of the upper valve device 58 will be depressed because of contact therewith by a portion of the gun battery-frame unit. Similarly, upon arrival of the gun battery at the prescribed maximum muzzleelevated position thereof the actuating stem portion of the lower valve 58 will be automatically depressed by contact therewith of a portion of the gun battery frame unit.

As illustrated in detail of Fig. 2, each of the valve devices 58-50 comprises a housing '54 which is bored to slidably accommodate a valve actuating stem 56. The stem is fitted with an enlarged contact head 58 backed up by a compression spring 59 which normally biases the stem 56 to extend as shown in Fig. 2 from the housing 54. At its opposite end the stem 56 carries an arm 60 which engages one end of a pin 62 which is also slidably mounted upon a bored portion of the housing 54 to extend substantially parallel to the stem 56. The pin 62 is threaded through a hydraulic fluid seal 64 backed up by a gland 66; and when the stem 56 is in its normal spring-biased position the pin 62 is thereby arranged to bear against ahydraulic check valve ball 16 which is contained within a fluid chamber 12 of the housing in such manner as to force the ball away from an annular valve seat 14. At the opposite Side of the ball 70 a cylindrical cage 16 bears against the ball and is slidably mounted within the housing 54 to move with the ball toward and away from valve seat contacting position. A compression spring 88 is mounted within the housing 54 by means of a screw 82 to press upwardly against the cage 16 so as to tend to seat the valve 10 against the annulus 14. The springs 59-80 are so provided however as to enable the spring 59 to overcome the force of the spring 80 unless otherwise restrained, whereby the pin 62 will normally be actuated to hold the ball 10 in unseated position as shown in Fig. 2. Hydraulic fluid inlet-outlet ports 84-86, respectively are formed in the housing 54 in communication with the fluid chamber 12 at opposite sides of the valve seat 14. The conduit 41 leading from the generator 40 is connected into open communication with the fluid port 84 of the upper valve 50. One end of another conduit 90 is connected in open communication with the fluid port 86 of the same valve device, and the other end of the conduit 96 is connected in open communication with the fluid port 36 of the lower valve device 50. One end of a third conduit 92 is connected in open communication with the fluid port 84 of the lower valve 58, and the other end of the conduit 92 is connected into one of the fluid ports of the motor 30. The conduit 46 leading from the generator 40 connects into the other fluid port of the motor 36; thus providing a closed circuit fluid transmission system including, in series: the generator 40; the valves 50-50; and the motor 30.

As illustrated, the generator and valve and motor system is so arranged that, for example, when the control handle 45 is manually twisted forwardly and downwardly the valve mechanism 44 is thereby adjusted so as to cause fluid under pressure to be directed to flow from the generator 40 through the conduit 41 into the port 84 of the upper valve 56. Assuming that the control motion of the handle 45 referred to hereinabove is applied when the gun battery is in a substantially neutral or horizontal attitude as viewed in Fig. l, the actuating stems 58-58 of both the upper and lower valves 58-56 will be free from contact with the gun mount port, and the valve devices 50-50 will therefore be disposed in the positions thereof as illustrated in Fig. 2. Consequently, the pressured fluid will be free to flow through the upper valve 50 from the port 84 and through the valve seat l4 and thence into the conduit 90 leading to the lower valve 50. The fluid will thereupon flow through the port 65 of the lower valve and then through the valve seat 14 thereof and out of the port 84 into the conduit 92 leading to the motor 38. The fluid Will then flow through the motor 30 in such direction as to actuate the motor to rotate the gun mount frame 22 in counter-clockwise direction as viewed in Fig. 1 about the axis of the bearings 26-26, so as to depress the gun battery aim in consonance with the manual depression of the control handle 45 referred to hereinabove.

As long as the control handle 45 is held in the depressed inclination referred to, the hydraulic fluid will tend to flow from the generator 40 through the motor 30 in the manner referred to, and the gun battery will continue to rotate for elevational aim adjustment purposes as described. However, upon arrival of the gun battery at the predetermined lower limit of un barrel depression, as indicated by relative positions of other structural elements of the aircraft or the like, the gun battery aiming movement referred to must be stopped just prior to any physical bearing of the gun barrel mechanism or the like against the interfering structures. As explained in the specification hereinabove, the upper valve 50 is mounted upon the bracket 32 in such manner that upon arrival of the gun battery at the predetermined maximum muzzle-depressed position thereof, the gun mount frame 22 will bear against the actuating stem 58 of the upper valve in such manner as to withdraw the pin 62 thereof away from the valve ball 10. This will permit the spring to move the valve ball 10 into fluid sealing position against the valve seat 14, whereupon the circulation of pressured fluid referred to hereinabove will be interrupted. Consequently, operation of the motor 30 and aim adjusting motion of the gun battery will be simultaneously stopped; and the motor 30 will remain inactive so long as the control handle 45 is left to remain either in a depressed attitude as referred to hereinabove or in its neutral position.

Upon manual twisting of the control handle 45 to lan upwardly inclined attitude, however, the valve mechanism 44 willbethereby adjusted so as to direct fluid to flow under pressure from the generator 40 through the conduit 46 and through the mtor'39 indirection reverse to the previously referred to flow of fluid through the motor. Consequently, the fluid pressure forces will then tend to circulate fluid through the hydraulic system so as to pass through the still open lower valve 50 and thence through the conduit 9i) so as to enter the upper valve 59 through the port '85 thereof to apply fluid' pressure forces against its valve ball 10 in opposition to the forces of the spring Bill. The fluid pressure .foroe system and the valve spring 86 are provided so as to be of such relative strength that the reverse flow pressure forces referred to are capable of unseating the valve ball is against the action of the spring 80. Consequently, under such condi tions of adjustment of the control handle 45 the fluid pressure force system will operate in reverse direction to immediately commence elevation of the gun battery aim. The gun battery will thereupon back away from bearing relation against the upper valve stem 58, whereby the spring .59 will be enabled to actuate the pin .62 to maintain the upper valve unit positively in open condition. Thus, thegun battery aim elevating movement will continue if the control handle i5 is maintained in upwardly twisted attitude, but only until the gun battery reaches the predetermined maximum muzzle-elevated position thereof, whereupon the gun battery frame will impinge against the actuating stem 58 of the lower valve 59. This will permit the valve ball 7-0 to seat itself so as to stop the elevating'movemerit of the gun battery in a manner identical to the operation .of the upper valve to as explained hereinabove.

Therefore, the hydraulic control system will again be in condition to be adjusted to operate in reverse direction only upon subsequent manipulation of the control handle 5 to a downwardly tilted attitude; andthat the hydraulic control system of the invention is therefore provided to control the gun battery to move upon the bearings 26-26 for elevational aim adjustment purposes in direct consonance with similar movements of the control handle 45 as applied manually by the gun battery attendant. Thus, it will be appreciated that the automatic aim movement stop means of the invention is adapted to function to positively limit the aim adjusting movements of the gun battery without involving mechanical interferences of parts of the mechanism such as might otherwise bind or look the mechanism in stopped positions, or impose undue wear upon the control mechanism. It will be understood that although the automatic stop means of the invention has been illustrated and described herein only in connection with the elevational aim adjustment mechanism of the gun battery, it may be applied if desired with equal facility to control the operation of the azimuth control motor 28; and that the stop mechanisms referred to may also be employed to provide the features and advantages of the invention in conjunction with other types of gun mounts and aim adjusting devices.

I claim:

1. In a gun aiming hydraulic power supply system for stopping the movement of a gun at predetermined limits including a fluid circuit, a normally open circuit interruption valve comprising a housing having a fluid passageway therethrough in normally open series communication with the fluid circuit, a valve seat disposed intermediately of said passageway, a valve disposed within said passageway and adapted to move between seated and unseated positions to alternately close and open said valve device for .controlled fluid passage purposes, a spring tending to bias said valve toward seated position, and push rod means extending from exteriorly of said housing into said fiuid passageway portion to register in abutting relationwith said valve for forcibly unseating the latter against the action of said spring, said push rod being arranged to be actuated by the gun upon its arrival at a predetermined position, whereby the fluid to said motor will be interrupted by the actuated valve.

2. A hydraulic motor system for moving a gun to be aimed, said system including a pressure generator and a motor adapted to be connected to a gun for aiming purposes, said hydraulic system including a stop valve device comprising a housing having a fluid passageway therethrough, a valve seat disposed intermediately of said passageway, a valve disposed within said passageway and adapted to move between seated and unseated positions to close and open said valve device for controlled fluid passage purposes, a spring tending to bias said valve toward seated position, a push rod extending from .extcriorly of said housing to register with said valve, means normally biasing said push rod for forcibly unseating said valve against the action of said spring, said push rod being arranged to be actuated by the gun upon its arrival at a predetermined position whereby said valve will be released so asto be subjected to the action of said spring to interrupt the flow of fluid to said motor.

3. A hydraulic pressure system for moving .a gun for aiming purposes, said system including a motor adapted to be connected to the gun for gun aim purposes, and a stop valve device comprising a normally open spring-biased check valve connected in normally open communication with said motor and a push rod extending from exterior-1y of said check valve to register with the valve element thereof, and means normally biasing said push rod for forcibly unseating said valve element against the action of its spring, said push rod being arranged to be actuated by the gun upon its arrival at a predetermined osition, whereby the fluid to said motor will be interrupted by the actuated stop valve device.

4. A hydraulic pressure conduit system for actuating a gun for aiming purposes, said system including a motor for driving the gun for aiming purposes, and a normally open stop valve device comprising a housing having a fluid passageway therethrough, a valve seat disposed adjacent said passageway, a valve member disposed to move against said seat to close said valve device against flow of fluid through said passageway, means tending to bias said valve toward seated position, and push means extending from exteriorly of said housing to register with said valve for forcibly unseating the latter against the action of said biasing means, said push means being arranged to be actuated by the gun upon its arrival at a predetermined position, whereby the fluid to said motor will be interrupted by the actuated stop valve device.

5. A hydraulic conduit system for actuating a gun for aiming purposes, said system including in series; a reverse direction hydraulic pressure generator; a reverse direction motor for driving a gun for gun aim purposes; a control device for adjusting said generator to discharge fluid under pressure to circulate through said conduit system in opposite directions; and a stop valve device adjacent the limit of gun movement in each direction, each of said stop valve devices comprising a housing having a fluid passageway therethrough in normally open series communication with said conduit system, a Valve seat disposed adjacent said passageway, a valve disposed to move between seated and unseated positions to alternately close and open said valve device for controlled fluid passage purposes, a spring tending to bias said valve toward seated position, and push rod means extending from exteriorly of said housing to register with said valve and normally biased for forcibly unseating the valve against the action of said spring, said push rod being arranged to be actuated by the gun upon its arrival at predetermined opposite positions, whereby said valves and springs are released and said valve devices are freed to operate as check valve devices.

6. A hydraulic conduit system for actuating a gun for aiming purposes, said system including a reversible motor for connection to a gun for gun aim purposes, said hydraulic system including a pair of normally open stop valve devices in normally open series communication with said motor, each device comprising a spring-biased check valve, push means extending from exteriorly of said check valve to register with the valve element thereof, and means normally biasing said push means for forcibly unseating said valve element against the action of its spring, said push means being arranged to be actuated by the gun upon its arrival at opposite predetermined positions, whereby the fluid to said motor will be interrupted by the actuated stop valve device.

7. In a hydraulic gun training system, a reversible hydraulic pressure generator, 2. reversible motor for connection to a gun for gun training purposes, a pair of stop valv devices arranged one at each end of the gun aiming travel, conduit means connecting said generator, said motor, and said valve devices in series with each other in a fluid-tight system, means for directing the fluid in said system from said generator in either direction through the conduit and associated means, each of said valve devices comprising a housing having a fluid passageway therethrough in open communication with said system, a valve seat disposed intermediately of said passageway, a valve disposed within said passageway and adapted to be moved between seated and unseated positions to close and open said valve devices for controlled fluid passage purposes, a spring tending to bias said valve toward seated position, a push rod extending from exteriorly of said housing to register with said valve and normally biased for forcibly unseating the valve against the action of said spring, one of said push rods being arranged to be actuated by the gun upon its arrival at either end of predetermined aiming travel, whereby the spring and said valve of the actuated devices will be released and the device free to operate as a check valve device.

8. In a fluid-tight gun training system, a gun mounted for swinging movement between two predetermined positions, a, pair of valve devices connected in said system in series with each other for alternate opening and closing to interrupt the flow of fluid in said system, each valve comprising a, housing having a fluid passageway therethrough for normal uninterrupted communication with said system, a valve seat disposed intermediately of said passageway, a valve disposed within said passageway and adapted to move between seated and unseated positions to alternately close and open said valve device for controlled fluid passage purposes, a valve spring tending to normally bias said valve toward seated position, push rod means extending from exteriorly of said housing into said fluid passageway portion to register in abutting relation with said valve for forcibly unseating the latter against the action of said valve spring, and an actuating stem slidably carried by said housing and attached to the exposed end of said rod, a stem spring tending to bias said stem toward normal operative position, said stem spring also serving to counteract said valve spring to normally maintain said valve in open position, said actuating stem having an operating portion extending exteriorly of said housing for engagement by the gun upon its arrival at oppositely arranged predetermined positions in said movement thereof.

JOHN C. TROTTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 16,695 Heywood Aug. 9, 1927 1,071,271 Spangler Aug. 26, 1913 1,289,692 Dawson et al Dec. 31, 1918 1,329,209 Riccio Jan. 27, 1920 1,573,354 Methlin Feb. 16, 1926 1,774,035 Osgood Aug. 26, 1930 2,233,918 Fey Mar. 4, 1941 2,247,842 Kamenarovic July 1, 1941 2,256,589 Bryant Sept. 23, 1941 FOREIGN PATENTS Number Country Date 476,590 Great Britain Dec. 13, 1937 489,208 Great Britain July 21, 1938 787,298 France July 1, 1935 

